| 摘要 |
<p>PURPOSE:To apply optimum power to the resistance values of the heating wires of each joint even when the resistance values differ, and to enable electric fusion positively and efficiently by controlling the duty ratio of a power supply applied to the heating wires of the joints and overall conduction time. CONSTITUTION:A light pen 28 for reading a bar code label 26 attached to a joint 24 is connected to a connector 22. A microcomputer 68 interrupts a control signal to the output port of the microcomputer 68 in response to a duty ratio D and the conduction time T set. Since the control signal is amplified and applied to the base of a switching transistor 62, the switching transistor 62 repeats ON/OFF according to the duty ratio D set, and the ON/OFF is continued only for the conduction time T set.</p> |
